1. Field of the Invention
The present invention relates to an apparatus and method for compressing a header of a packet and, more specifically, to an apparatus and method for compressing a header of a packet wherein a delay of packet transmission and a storage area which is wasted unnecessarily are removed by determining an IP header compression of a generated packet using property information of a socket used to transmit data generated in an application layer to an OS (Operation System) layer.
2. Description of the Related Art
Recently, a request for transmitting video or audio data through a network in real time increases.
To satisfy such request, RTP (Real-time Transport Protocol) is prescribed in Network Working Group RFC 1889 (Request For Comment 1889) published by IETF (Internet Engineering Task Force) which is an Internet standardization organization, and the RTP is used to transmit the audio or video data through the network in real time. RTP provides end-to-end network transport functions suitable for applications transmitting real-time data, such as audio, video or simulation data, over multicast or unicast network services.
An IP (Internet Protocol) header added to be transmitted in real time through the network according to the RTP has 20 bytes, a UDP (User Datagram Protocol) header has 8 bytes, and an RTP header has 12 bytes.
Accordingly, since an over header for a packet used to transmit one of data is generated, IPCP (IP Compression Protocol), CRTP (Compression RTP) and ROHC(RObust Header Compression) are prescribed in order to solve such problem.
The IPCP is a technique to compress RTP/UDP/IP header, UDP/IP header and ESP (Encapsulation Security Payload)/IP header, and CRTP and ROHC are techniques to compress IP/UDP/RTP header.
Network Working Group RFC 2507 describes how to compress multiple IP headers and TCP and UDP headers per hop over point to point links. Network Working Group RFC 2508 describes a method for compressing the headers of IP/UDP/RTP datagrams to reduce overhead on low-speed serial links.
U.S. Pat. No. 6,314,095 B1 to Kanchei Loa and entitled METHOD AND